from bokeh.palettes import Spectral5
from bokeh.sampledata.autompg import autompg as df
from bokeh.transform import factor_cmap
from bokeh.sampledata.autompg import autompg_clean as df
from bokeh.plotting import figure, show


def mpg():
    df.cyl = df.cyl.astype(str)
    # df.cyl = df.cyl.astype(str)
    group = df.groupby(['cyl', 'mfr'])
    index_cmap = factor_cmap('cyl_mfr', palette=Spectral5, factors=sorted(df.cyl.unique()), end=1)
    # 画布
    p = figure(plot_width=800, plot_height=350, title="MEAN mpg by #cylinders and manu facturer",
               x_range=group, tooltips=[("MPG", "@mpg_mean"), ('cyl,Mfr', "cyl_mfr")]
               )
    # 柱状图
    p.vbar(x='cyl_mfr', top='mpg_mean', width=1, source=group,
           line_color="white", fill_color=index_cmap, )
    # 其他
    p.y_range.start = 0
    p.x_range.range_padding = 0.05
    p.xgrid.grid_line_color = None

    p.xaxis.major_label_orientation = 1.2  # x轴标签旋钮
    p.xgrid.grid_line_color = None

    return p
